# Why can't I execute other commands while the dialog is running?

Bug introduced in v10.4 or earlier and persisting through 11.3

CASE:4226661

The code is from the following video: http://www.wolfram.com/broadcast/video.php?sx=Ian%20Johnson&v=2076

CreateDialog[
DynamicModule[{
vals={}
},
Column[{
Dynamic@ListLinePlot[
vals=Reverse@Take[Reverse@vals,UpTo[300]],
Filling->Axis,
AxesLabel->{"Time","Memory (GB)"},
Ticks->{None,Automatic},
PlotRange->{0,QuantityMagnitude@UnitConvert[SystemInformation["Machine","PhysicalTotal"],"Gigabytes"]},
ImageSize->Medium
],
Dynamic@Refresh[
AppendTo[vals,SystemInformation["Machine","PhysicalTotal"]-SystemInformation["Machine","PhysicalUsed"]]//Last,
UpdateInterval->1.5
]
},
Alignment->Center
]
],
WindowFloating->True,
WindowClickSelect->True,
Modal->False
]


In the video the speaker run the above command and then executes the following:

• x=Range[500000000];2;
• ClearAll[x];

To show how the dialog notes the changes in memory available when storing the expression. But when I run the command it opens the new notebook (dialog) but does not allow me to execute the other command while the dialog is running.

It is a bug related to WindowFloating->True on Windows. I reported it recently.
Use WindowFloating->False or drop it and everything will be ok.